<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Document</title>
  <style>
    #box1 {
      width: 300px;
      height: 300px;
      background-color: red;
    }

    #box2 {
      width: 200px;
      height: 200px;
      background-color: green;
    }

    #box3 {
      width: 100px;
      height: 100px;
      background-color: blue;
    }
  </style>
</head>
<body>
  <div id="box1">
    <div id="box2">
      <div id="box3">
      </div>
    </div>
  </div>
  <script>
    // 事件冒泡
    var box1 = document.getElementById('box1');
    var box2 = document.getElementById('box2');
    var box3 = document.getElementById('box3');

    var array = [box1, box2, box3];

    for (var i = 0; i < array.length; i++) {
      var box = array[i];
      box.onclick = function (e) {
        console.log(this.id);
        // Propagation 传播
        // 停止事件传播  取消冒泡
        // 标准的DOM方法
        // e.stopPropagation();
        
        // 取消冒泡  非标准的方式 老版本的IE支持
//        e.cancelBubble = true;
      }
    }
   

  </script> 
</body>
</html>
